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1.
Polymers (Basel) ; 16(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732658

RESUMO

Smart polymeric micelles (PMs) are of great interest in drug delivery owing to their low critical micellar concentration and sizes. In the present study, two different pH-sensitive poly(2-vinyl pyridine)-b-poly(ethylene oxide) (P2VP-b-PEO) copolymer samples were used for the encapsulation of paclitaxel (PTX), ursolic acid (UA), and dual loading of PTX and UA. Based on the molecular features of copolymers, spherical PMs with sizes of around 35 nm and 140 nm were obtained by dialysis for P2VP55-b-PEO284 and P2VP274-b-PEO1406 samples, respectively. The micellar sizes increased after loading of both drugs. Moreover, drug encapsulation and loading efficiencies varied from 53 to 94% and from 3.2 to 18.7% as a function of the copolymer/drug ratio, molar mass of copolymer sample, and drug type. By FT-IR spectroscopy, it was possible to demonstrate the drug loading and the presence of some interactions between the polymer matrix and loaded drugs. In vitro viability was studied on 4T1 mammary carcinoma mouse cells as a function of time and concentration of drug-loaded PMs. UA-PMs and free PMs alone were not effective in inhibiting the tumor cell growth whereas a viability of 40% was determined for cells treated with both PTX- and PTX/UA-loaded PMs. A synergic effect was noticed for PTX/UA-loaded PMs.

2.
Brain ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662500

RESUMO

Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in five times familial AD (5XFAD) mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages, and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissue from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2), and the excitatory NMDA and AMPA type glutamate receptors. We performed patch clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and had decreased GABAA receptor subunit expression, and increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced ß-amyloid pathology and cognitive deficits, could also reverse elevations to NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with FDA-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.

3.
Eur J Neurosci ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654472

RESUMO

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is caused by a loss-of-function mutation in CDKL5 gene, encoding a serine-threonine kinase highly expressed in the brain. CDD manifests with early-onset epilepsy, autism, motor impairment and severe intellectual disability. While there are no known treatments for CDD, the use of cannabidiol has recently been introduced into clinical practice for neurodevelopmental disorders. Given the increased clinical utilization of cannabidiol, we examined its efficacy in the CDKL5R59X knock-in (R59X) mice, a CDD model based on a human mutation that exhibits both lifelong seizure susceptibility and behavioural deficits. We found that cannabidiol pre-treatment rescued the increased seizure susceptibility in response to the chemoconvulsant pentylenetetrazol (PTZ), attenuated working memory and long-term memory impairments, and rescued social deficits in adult R59X mice. To elucidate a potential mechanism, we compared the developmental hippocampal and cortical expression of common endocannabinoid (eCB) targets in R59X mice and their wild-type littermates, including cannabinoid type 1 receptor (CB1R), transient receptor potential vanilloid type 1 (TRPV1) and 2 (TRPV2), G-coupled protein receptor 55 (GPR55) and adenosine receptor 1 (A1R). Many of these eCB targets were developmentally regulated in both R59X and wild-type mice. In addition, adult R59X mice demonstrated significantly decreased expression of CB1R and TRPV1 in the hippocampus, and TRPV2 in the cortex, while TRPV1 was increased in the cortex. These findings support the potential for dysregulation of eCB signalling as a plausible mechanism and therapeutic target in CDD, given the efficacy of cannabidiol to attenuate hyperexcitability and behavioural deficits in this disorder.

4.
J Clin Invest ; 134(5)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227384

RESUMO

Early-life seizures (ELSs) can cause permanent cognitive deficits and network hyperexcitability, but it is unclear whether ELSs induce persistent changes in specific neuronal populations and whether these changes can be targeted to mitigate network dysfunction. We used the targeted recombination of activated populations (TRAP) approach to genetically label neurons activated by kainate-induced ELSs in immature mice. The ELS-TRAPed neurons were mainly found in hippocampal CA1, remained uniquely susceptible to reactivation by later-life seizures, and displayed sustained enhancement in α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated (AMPAR-mediated) excitatory synaptic transmission and inward rectification. ELS-TRAPed neurons, but not non-TRAPed surrounding neurons, exhibited enduring decreases in Gria2 mRNA, responsible for encoding the GluA2 subunit of the AMPARs. This was paralleled by decreased synaptic GluA2 protein expression and heightened phosphorylated GluA2 at Ser880 in dendrites, indicative of GluA2 internalization. Consistent with increased GluA2-lacking AMPARs, ELS-TRAPed neurons showed premature silent synapse depletion, impaired long-term potentiation, and impaired long-term depression. In vivo postseizure treatment with IEM-1460, an inhibitor of GluA2-lacking AMPARs, markedly mitigated ELS-induced changes in TRAPed neurons. These findings show that enduring modifications of AMPARs occur in a subpopulation of ELS-activated neurons, contributing to synaptic dysplasticity and network hyperexcitability, but are reversible with early IEM-1460 intervention.


Assuntos
Adamantano/análogos & derivados , Convulsões , Animais , Camundongos , Convulsões/genética , Neurônios , Hipocampo , Receptores de AMPA/genética
6.
Immun Inflamm Dis ; 11(8): e909, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37647421

RESUMO

We have appreciated the article published by Bardsley and colleagues describing the seasonal circulation of respiratory syncytial virus (RSV) in UK children, and we hope to contribute to increase information on this intriguing and elusive topic. We describe our epidemiological trend with the aim to add a small brick to the current knowledge regarding respiratory infections due to RSV and other respiratory viruses in an era that is changing due to a radical change in the evaluation of respiratory symptoms following the pandemic event.


Assuntos
Pandemias , Infecções Respiratórias , Criança , Humanos , Centros de Atenção Terciária , Vírus Sinciciais Respiratórios , Infecções Respiratórias/epidemiologia
7.
Epilepsia Open ; 8(3): 834-845, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37052238

RESUMO

OBJECTIVE: As of 2022, 36 anti-seizure medications (ASMs) have been licensed for the treatment of epilepsy, however, adverse effects (AEs) are commonly reported. Therefore, ASMs with a wide margin between therapeutic effects and AEs are preferred over ASMs that are associated with a narrow margin between efficacy and risk of AEs. E2730 was discovered using in vivo phenotypic screening and characterized as an uncompetitive, yet selective, inhibitor of γ-aminobutyric acid (GABA) transporter 1 (GAT1). Here, we describe the preclinical characteristics of E2730. METHODS: Anti-seizure effects of E2730 were evaluated in several animal models of epilepsy: corneal kindling, 6 Hz-44 mA psychomotor seizure, amygdala kindling, Fragile X syndrome, and Dravet syndrome models. Effects of E2730 on motor coordination were assessed in accelerating rotarod tests. The mechanism of action of E2730 was explored by [3 H]E2730 binding assay. The GAT1-selectivity over other GABA transporters was examined by GABA uptake assay of GAT1, GAT2, GAT3, or betaine/GABA transporter 1 (BGT-1) stably expressing HEK293 cells. To further investigate the mechanism for E2730-mediated inhibition of GAT1, in vivo microdialysis and in vitro GABA uptake assays were conducted under conditions of different GABA concentrations. RESULTS: E2730 showed anti-seizure effects in the assessed animal models with an approximately >20-|fold margin between efficacy and motor incoordination. [3 H]E2730 binding on brain synaptosomal membrane was abolished in GAT1-deficient mice, and E2730 selectively inhibited GAT1-mediated GABA uptake over other GABA transporters. In addition, results of GABA uptake assays showed that E2730-mediated inhibition of GAT1 positively correlated to the level of ambient GABA in vitro. E2730 also increased extracellular GABA concentration in hyperactivated conditions but not under basal levels in vivo. SIGNIFICANCE: E2730 is a novel, selective, uncompetitive GAT1 inhibitor, which acts selectively under the condition of increasing synaptic activity, contributing to a wide margin between therapeutic effect and motor incoordination.


Assuntos
Anticonvulsivantes , Epilepsia , Proteínas da Membrana Plasmática de Transporte de GABA , Animais , Humanos , Camundongos , Ataxia , Epilepsia/tratamento farmacológico , Proteínas da Membrana Plasmática de Transporte de GABA/administração & dosagem , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/metabolismo , Células HEK293 , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico
8.
Epilepsy Behav ; 143: 109194, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37119576

RESUMO

Early-life seizures can be refractory to conventional antiseizure medications (ASMs) and can also result in chronic epilepsy and long-term behavioral and cognitive deficits. Treatments targeting age-specific mechanisms contributing to epilepsy would be of clinical benefit. One such target is the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subtype of excitatory glutamate receptor, which is upregulated in the developing brain. Perampanel is a non-competitive, selective AMPAR antagonist that is FDA-approved for focal onset seizures (FOS) or primary generalized tonic-clonic seizures (PGTC) in children and adults. However, the efficacy of perampanel treatment in epilepsy patients younger than 4 years has been less documented. We thus tested the efficacy of perampanel in two early-life seizure models: (1) a rat model of hypoxia-induced neonatal seizures and (2) a mouse model of Dravet syndrome with hyperthermia-induced seizures. Pretreatment with perampanel conferred dose-dependent protection against early-life seizures in both experimental models. These findings suggest that AMPAR-mediated hyperexcitability could be involved in the pathophysiology of early-life seizures, which may be amenable to treatment with perampanel.


Assuntos
Epilepsia , Roedores , Camundongos , Ratos , Animais , Anticonvulsivantes/efeitos adversos , Resultado do Tratamento , Epilepsia/tratamento farmacológico , Piridonas
10.
Metabolites ; 12(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36144191

RESUMO

A substantial decline in nicotinamide adenine dinucleotide (NAD) has been reported in brain tissue homogenates or neurons isolated from Alzheimer's disease (AD) models. NAD, together with flavin adenine dinucleotide (FAD), critically supports energy metabolism and maintains mitochondrial redox homeostasis. Optical redox imaging (ORI) of the intrinsic fluorescence of reduced NAD (NADH) and oxidized FAD yields cellular redox and metabolic information and provides biomarkers for a variety of pathological conditions. However, its utility in AD has not been characterized at the tissue level. We performed ex vivo ORI of freshly dissected hippocampi from a well-characterized AD mouse model with five familial Alzheimer's disease mutations (5XFAD) and wild type (WT) control littermates at various ages. We found (1) a significant increase in the redox ratio with age in the hippocampi of both the WT control and the 5XFAD model, with a more prominent redox shift in the AD hippocampi; (2) a higher NADH in the 5XFAD versus WT hippocampi at the pre-symptomatic age of 2 months; and (3) a negative correlation between NADH and Aß42 level, a positive correlation between Fp and Aß42 level, and a positive correlation between redox ratio and Aß42 level in the AD hippocampi. These findings suggest that the ORI can be further optimized to conveniently study the metabolism of freshly dissected brain tissues in animal models and identify early AD biomarkers.

11.
Sci Total Environ ; 852: 158544, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36075421

RESUMO

Invasion by exotic grasses is transforming drylands across the planet, but the ecohydrological feedbacks of such invasions are not fully understood. For example, in the Sonoran Desert, previous studies have shown that buffelgrass (Cenchrus ciliaris) alters the spatial patterns of soil moisture, leading researchers to hypothesize that such alterations are related to the plants' effects on soil infiltrability. To evaluate this hypothesis, we compared field-saturated hydraulic conductivity (Kfs) in a native shrubland with that in a neighboring savanna extensively dominated by exotic buffelgrass. We measured Kfs during the dormant and growing seasons in both canopy and intercanopy zones. We found that Kfs was generally lower during the dormant season than during the growing season. There were no significant differences between sites during the dormant season, and at both sites, Kfs was 6-7 times higher under shrubs than in the intercanopies. During the growing season, Kfs for the exotic intercanopy was comparable to that for shrub cluster edges (140 mm h-1) and was more than twice that for the native intercanopy. Both shrubs and buffelgrass improved Kfs by reducing soil bulk density (thus increasing porosity). Additionally, surface roughness in the exotic intercanopy was nearly 3 times higher than in the native intercanopy. The combination of greater surface roughness and higher infiltration rates during the growing season most likely alters hydrological connectivity in savannas invaded by exotic grasses such as buffelgrass. By capturing portions of the runoff generated in the intercanopy, these grasses reduce runon into shrub patches, with potentially substantial impacts on native vegetation dynamics and stability.


Assuntos
Ecossistema , Solo , Poaceae , Plantas , Estações do Ano
12.
Cell Genom ; 2(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36177448

RESUMO

Molecular profiling studies have enabled discoveries for metastatic prostate cancer (MPC) but have predominantly occurred in academic medical institutions and involved non-representative patient populations. We established the Metastatic Prostate Cancer Project (MPCproject, mpcproject.org), a patient-partnered initiative to involve patients with MPC living anywhere in the US and Canada in molecular research. Here, we present results from our partnership with the first 706 MPCproject participants. While 41% of patient partners live in rural, physician-shortage, or medically underserved areas, the MPCproject has not yet achieved racial diversity, a disparity that demands new initiatives detailed herein. Among molecular data from 333 patient partners (572 samples), exome sequencing of 63 tumor and 19 cell-free DNA (cfDNA) samples recapitulated known findings in MPC, while inexpensive ultra-low-coverage sequencing of 318 cfDNA samples revealed clinically relevant AR amplifications. This study illustrates the power of a growing, longitudinal partnership with patients to generate a more representative understanding of MPC.

13.
Arch Med Sci ; 18(4): 881-889, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832699

RESUMO

Androgen insensitivity syndrome (AIS) is an X-linked recessive genetic syndrome that occurs as result of an androgen receptor mutation; it affects the normal masculinization process in chromosomal male patients. More than 900 androgen receptor mutations that can lead to AIS have been identified. The complete androgen insensitivity is characterized by a total lack of response to androgens, usually in patients with 46XY karyotype but with feminine phenotype. Primary amenorrhoea and inguinal swellings in female patients are the main signs that could raise suspicion for this syndrome. Patients with partial androgen insensitivity have ambiguous genitalia at birth and gynecomastia during puberty, whereas those with mild androgen insensitivity present a normal male phenotype but altered spermatogenesis during adulthood and pubertal gynecomastia. The diagnosis of AIS often proves to be a challenge; its management is complex and requires a multidisciplinary approach to meet decision-making challenges in sex assignment, fertility and timing of gonadectomy, psychological outcomes and genetic counselling.

14.
Cancers (Basel) ; 14(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35804962

RESUMO

In 2019, the Global Burden of Disease (GBD) estimated that prostate cancer (PC) was the 16th most common cause of death globally in males. In Mexico, PC epidemiology has been studied by a number of metrics and over various periods, although without including the most up-to-date estimates. Herein, we describe and compare the burdens and trends of PC in Mexico and its 32 states from 2000 to 2019. For this study, we extracted online available data from the GBD 2019 to estimate the crude and age-standardized rates (ASR per 100,000 people) of the incidence and mortality of PC. In Mexico, PC caused 27.1 thousand (95% uncertainty intervals, 20.6-36.0 thousand) incident cases and 9.2 thousand (7.7-12.7 thousand) deaths in males of all ages in 2019. Among the states, Sinaloa had the greatest ASR of incidence, and Guerrero had the highest mortality. The burden of PC showed an increasing trend, although the magnitude of change differed between metrics and locations. We found both an increasing national trend and subnational variation in the burden of PC. Our results confirm the need for updated and timely estimates to design effective diagnostic and treatment campaigns in locations where the burden of PC is the highest.

15.
Sci Total Environ ; 840: 156654, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35700776

RESUMO

Most methods for mapping groundwater vulnerability are based on the excessively simplistic approach that aquifer recharge is produced by vertical infiltration. The novel Land Use-Intrinsic Vulnerability (LU-IV) procedure assesses groundwater vulnerability to nitrate pollution over the entire territory, including aquifers catchment areas. In this research, it was analysed if the delineation of nitrate vulnerable zones (NVZs) would be improved by introducing a new parameter representing the risk associated with soil permeability (parameter S) in the procedure. Different versions of parameter S were tested: S_HC (risk associated with soil hydraulic conductivity), S_St+G+S (risk associated with the stone, gravel and sand fraction of the soil) and S_C (risk associated with the clay fraction). The study was undertaken in the catchment areas of the Oja and Tirón alluvial aquifers (Spain). The efficacy of the following six models was compared: Model 1 (original LU-IV procedure), Model 2 (LU-IV' procedure using parameter S_HC), Model 3 (LU-IV' procedure using parameter S_St+G+S), Model 4 (LU-IV' procedure using parameter S_C), Model 5 (LU-DRASTIC-COP procedure, based on DRASTIC-COP method), and Model 6 (designated NVZ). Catchment scale validations of the six models showed similar, highly significant correlations between the percent coverages of the estimated NVZs and those of the alluvial areas polluted by nitrate for Models 1 to 4. Models 5 and 6 did not show any significant results. In light of these results, Models 1 to 4 were considered the best predictors of nitrate pollution and the best methods for NVZ delineation. Results support the idea that including a parameter S in the LU-IV' procedure is not essential since equivalent results were obtained from the original LU-IV procedure. So, the LU-IV procedure should be considered the best and simplest method of those tested for accurately delineating NVZs.


Assuntos
Água Subterrânea , Nitratos , Monitoramento Ambiental/métodos , Nitratos/análise , Óxidos de Nitrogênio , Permeabilidade , Solo , Poluição da Água/análise
16.
Planta ; 256(1): 9, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35696004

RESUMO

MAIN CONCLUSION: The present review summarizes recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics, discusses its importance in plant genomes, and highlights its chemical nature and functions. Adenine methylation is an epigenetic modification present in DNA (6mA) and RNA (m6A) that has a regulatory function in many cellular processes. This modification occurs through a reversible reaction that covalently binds a methyl group, usually at the N6 position of the purine ring. This modification carries biophysical properties that affect the stability of nucleic acids as well as their binding affinity with other molecules. DNA 6mA has been related to genome stability, gene expression, DNA replication, and repair mechanisms. Recent advances have shown that 6mA in plant genomes is related to development and stress response. In this review, we present recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics. We discuss the key elements of this modification, focusing mainly on its importance in plant genomes. Furthermore, we highlight its chemical nature and the regulatory effects that it exerts on gene expression and plant development. Finally, we emphasize the functions of 6mA in photosynthesis, stress, and flowering.


Assuntos
Adenina , Metilação de DNA , DNA/genética , DNA/metabolismo , Metilação de DNA/genética , Epigênese Genética , Genoma de Planta/genética
17.
Cancers (Basel) ; 14(5)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35267575

RESUMO

The current risk stratification in prostate cancer (PCa) is frequently insufficient to adequately predict disease development and outcome. One hallmark of cancer is telomere maintenance. For telomere maintenance, PCa cells exclusively employ telomerase, making it essential for this cancer entity. However, TERT, the catalytic protein component of the reverse transcriptase telomerase, itself does not suit as a prognostic marker for prostate cancer as it is rather low expressed. We investigated if, instead of TERT, transcription factors regulating TERT may suit as prognostic markers. To identify transcription factors regulating TERT, we developed and applied a new gene regulatory modeling strategy to a comprehensive transcriptome dataset of 445 primary PCa. Six transcription factors were predicted as TERT regulators, and most prominently, the developmental morphogenic factor PITX1. PITX1 expression positively correlated with telomere staining intensity in PCa tumor samples. Functional assays and chromatin immune-precipitation showed that PITX1 activates TERT expression in PCa cells. Clinically, we observed that PITX1 is an excellent prognostic marker, as concluded from an analysis of more than 15,000 PCa samples. PITX1 expression in tumor samples associated with (i) increased Ki67 expression indicating increased tumor growth, (ii) a worse prognosis, and (iii) correlated with telomere length.

18.
Crit Care Nurs Clin North Am ; 34(1): 57-65, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35210025

RESUMO

Homeless individuals are seldom offered the opportunity to complete advance directives and designate decision makers. During a catastrophic illness, health care providers are left to do aggressive, life-prolonging treatments that the patient may not want while seeking decision makers who may not be familiar with the patient or what their wishes would be. The authors spearheaded a program to offer homeless individuals the opportunity to review and complete an advance directive and parlayed that work into a secondary project to provide a comfortable end-of-life experience for homeless patients.


Assuntos
Planejamento Antecipado de Cuidados , Pessoas Mal Alojadas , Diretivas Antecipadas , Audição , Humanos
19.
Brain ; 145(1): 324-339, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-34264340

RESUMO

The risk of seizures is 10-fold higher in patients with Alzheimer's disease than the general population, yet the mechanisms underlying this susceptibility and the effects of these seizures are poorly understood. To elucidate the proposed bidirectional relationship between Alzheimer's disease and seizures, we studied human brain samples (n = 34) from patients with Alzheimer's disease and found that those with a history of seizures (n = 14) had increased amyloid-ß and tau pathology, with upregulation of the mechanistic target of rapamycin (mTOR) pathway, compared with patients without a known history of seizures (n = 20). To establish whether seizures accelerate the progression of Alzheimer's disease, we induced chronic hyperexcitability in the five times familial Alzheimer's disease mouse model by kindling with the chemoconvulsant pentylenetetrazol and observed that the mouse model exhibited more severe seizures than the wild-type. Furthermore, kindled seizures exacerbated later cognitive impairment, Alzheimer's disease neuropathology and mTOR complex 1 activation. Finally, we demonstrated that the administration of the mTOR inhibitor rapamycin following kindled seizures rescued enhanced remote and long-term memory deficits associated with earlier kindling and prevented seizure-induced increases in Alzheimer's disease neuropathology. These data demonstrated an important link between chronic hyperexcitability and progressive Alzheimer's disease pathology and suggest a mechanism whereby rapamycin may serve as an adjunct therapy to attenuate progression of the disease.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Pentilenotetrazol/toxicidade , Convulsões/metabolismo
20.
Sci Total Environ ; 804: 150056, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798720

RESUMO

The role of land use and the physical environment in N and P pollution of alluvial aquifers was analysed at three levels of information: (1) aquifer (N and P in groundwater), (2) soil transect (potentially leachable N and P in the soil solution) and (3) aquifer's catchment area. The study was carried out in the Oja and Tirón alluvial aquifers and their catchment areas (northern Spain). Nitrate was the dominant N form, both in groundwater and the soil solution of aquifers' catchment areas. Orthophosphate and organic-P were the codominant P forms in the aquifers. Orthophosphate was the main form in the soil solution. During the period 2005-2017 no significant decrease in nitrate pollution was observed, suggesting the need to review current Nitrate Vulnerable Zone (NVZ) designations. Since nitrate is highly mobile, it tended to accumulate in stagnation zones at the lower reaches of the aquifers. P did not accumulate in the same zones due to its low solubility. Principal component analyses (PCAs) of the aquifers, soil transects and aquifers' catchment areas revealed that the observation scale influences the environmental factors that can be detected as intervening in groundwater pollution. At the aquifer scale, links were found between nitrates and land use, topographic, hydrogeological and climatic factors. The protective effect of natural areas against nitrate pollution was noteworthy, while agriculture was associated with pollution. At the soil transect scale, an altitudinal gradient governed soil particle size distribution and land use, separating mountain forest soils from agricultural soils. The negative relationship between clay contents vs. nitrate and orthophosphate in the soil solution pointed to a regulatory role of clay. At the catchment scale, the size and physical characteristics of the catchments and land use distribution determined macronutrient availability in the soil solution and, in turn, N and P groundwater distribution.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Nitratos/análise , Solo , Poluentes Químicos da Água/análise
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